Good news for people who don’t have hours to devote to working out: a
new study finds that short bouts of intense exercise can lower diabetes
and heart disease risk.

Current exercise recommendations for keeping a healthy heart and
reducing the chance of diabetes involve a hefty time commitment: 30
minutes or more of moderate intensity aerobic exercise on most days is
more than some people can manage. Even when it’s broken up, many people
find it difficult to squeeze exercise time into lives filled with
demands of work and family.

“There is no consensus on the nature of exercise therapy required to
provide adequate health benefits, particularly with regard to the
volume-intensity relationship,” said the study’s authors.
Less is more (than expected).

The study took a fresh approach to exercising for disease prevention.
Sixteen inactive men in their early twenties took part in the program,
which consisted of short, all-out bouts of sprinting on a stationary
bicycle alternating with periods of rest. During each session, the men
sprinted for 30 seconds against a resistance of about 7.5% of their body
weight, and then they either rested or cycled slowly for four minutes,
followed by another three to five repetitions of the sprint/rest
sequence. They repeated the sessions three times each week, bringing the
grand total of time spent actively exercising to 7½ minutes per week
(or about 20 minutes, three times per week, including the rest time).

Following two weeks of exercise training, the men showed
significantly better insulin sensitivity compared with the beginning of
the study, meaning that their ability to process sugar (glucose) from a
meal improved by adhering to the program. Three other measures of
glucose metabolism also improved, demonstrating that short bouts of
intense exercise can have a profound effect on cardiovascular and
diabetes risk factors.

“This novel time-efficient training paradigm can be used as a
strategy to reduce metabolic risk factors in young and middle-aged
sedentary people who otherwise would not adhere to time consuming
traditional exercise regimens,” the authors concluded.

Putting it in perspective

While it might be tempting to forget all the other information that
you’ve read about exercise and disease prevention in light of the new
study, keep this in mind: the men did not lose weight, so if that’s one
of your goals, you’ll still need to spend time working off those extra
pounds. Also, this was one small study; larger, more detailed trials
will need to confirm these promising results.

(BMC Endocrine Disorders 2009;9:doi10.1186/1472-6823-9-3)

Kimberly Beauchamp, ND, earned her bachelor’s
degree from the University of Rhode Island and her Doctorate of
Naturopathic Medicine from Bastyr University in Kenmore, WA. She
cofounded South County Naturopaths in Wakefield, RI, and now sees
patients in East Greenwich and Wakefield. Inspired by her passion for
healthful eating and her own young daughters, Dr. Beauchamp is currently
writing a book about optimizing children’s health through better
nutrition.